I've looked over the internet with various searches and haven't had luck nailing down a solution to this problem. I have a Site-to-Site IPSEC VPN between a remote location and the office. The remote location has a Cisco RV180w with the latest firmware. The office, using a TP-LINK TL-ER604W router.
The VPN is linked and I can access file shares, remote desktop without a challenge. The problem seems to be with Audio using an IP phone.
* Office to Remote calling works, we can hear each other.
* Remote to Office calling, they can hear me but I cannot hear them.
* Remote Calling to any number works, same issues: I can hear them, they cannot hear me.
* Access to Voice Mail using Softkeys - connects, I can hear the prompts - but key tones (DTMF) are not functioning to go through Voicemail
Remote Location Setup
VLAN 1: 10.50.0.0/24
VLAN 2: 192.168.55.0/ /24
VLAN 3: 10.80.80.0 /24 (used to connect to VPN)
Routing Mode : Gateway (NAT)
Routing Table: see attached file
Firewall Access Rules: Allow all, Block specified (nothing set)
Port Forwarding: None
SIP ALG: Enabled
This router is behind an ISP router, used for IPTV and Internet. The DMZ is enabled and set to the static IP on the WAN side of 192.168.2.253.